1. The speed of the roller coaster car at point B and C: are 19.8 m/s and 0 m/s respectively.
2. If mass (m) of the roller coaster car were doubled, the speed at B would increase because energy is dependent on the mass of an object.
Given the following data:
- Mass of roller coaster car = 750 kg
- Speed of roller coaster car = 15 m/s
1. To find the speed of the roller coaster car at point B and C:
First of all, we would determine the potential energy of the roller coaster car by using the formula:
[tex]P.E = mgh[/tex]
Where:
- g is the acceleration due to gravity ([tex]9.8\;m/s^2[/tex]).
- h is the height of an object.
From the diagram, height at point B = [tex]\frac{h}{2} = \frac{40}{2} = 20[/tex] meters
[tex]P.E = 750(9.8)(20)[/tex]
P.E = 147000 Joules.
Next, we would determine the speed by applying the law of conservation of energy.
[tex]Kinetic\;energy = Potential\;energy\\\\\frac{1}{2} mv^2 = mgh[/tex]
Substituting the values, we have;
[tex]147000 = \frac{1}{2} (750)v^2\\\\147000 = 375v^2\\\\v^2 = \frac{147000}{375} \\\\v^2 = 392\\\\v = \sqrt{392}[/tex]
Speed, v = 19.8 m/s
From the diagram, at point C, the speed is equal to zero (0) meters per seconds.
2. If mass (m) of the roller coaster car were doubled, the speed at B would increase because energy is dependent on the mass of an object.
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